To chip in as a "rubber strap" guy, I will always prefer FKM (fluoroelastomer-high-density-rubber) rubber strap. This kind of rubber is structurally higher in heat and chemical resistant. When worn on wrist, it will feel more flexible, pliant and softer compared to the normal rubber strap.
Few known brands that uses FKM rubber (not sure if all models are using these) - Zenith, Hublot, Sinn..